diff options
| -rw-r--r-- | sysdeps/unix/sysv/linux/powerpc/powerpc64/arch-pkey.h | 55 | ||||
| -rw-r--r-- | sysdeps/unix/sysv/linux/powerpc/powerpc64/pkey_get.c | 42 | ||||
| -rw-r--r-- | sysdeps/unix/sysv/linux/powerpc/powerpc64/pkey_set.c | 48 |
3 files changed, 145 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/arch-pkey.h b/sysdeps/unix/sysv/linux/powerpc/powerpc64/arch-pkey.h new file mode 100644 index 0000000000..623b073d5a --- /dev/null +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/arch-pkey.h @@ -0,0 +1,55 @@ +/* Helper functions for manipulating memory protection keys, for powerpc64. + Copyright (C) 2017-2020 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#ifndef _ARCH_PKEY_H +#define _ARCH_PKEY_H + +/* Read and write access bits in the AMR register. Needs to be + translated from and to PKEY_DISABLE_* flags. */ +#define PKEY_AMR_READ 1UL +#define PKEY_AMR_WRITE 2UL + +/* Return the value of the AMR register. */ +static inline unsigned long int +pkey_read (void) +{ + unsigned long int result; + __asm__ volatile ("mfspr %0, 13" : "=r" (result)); + return result; +} + +/* Overwrite the AMR register with VALUE. */ +static inline void +pkey_write (unsigned long int value) +{ + __asm__ volatile ("mtspr 13, %0" : : "r" (value)); +} + +/* Number of the largest supported key. This depends on the width of + the AMR register. */ +#define PKEY_MAX (sizeof (unsigned long int) * 8 / 2 - 1) +_Static_assert (PKEY_MAX == 15 || PKEY_MAX == 31, "PKEY_MAX value"); + +/* Translate key number into AMR index position. */ +static inline int +pkey_index (int key) +{ + return 2 * (PKEY_MAX - key); +} + +#endif /* _ARCH_PKEY_H */ diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/pkey_get.c b/sysdeps/unix/sysv/linux/powerpc/powerpc64/pkey_get.c new file mode 100644 index 0000000000..856ba061b9 --- /dev/null +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/pkey_get.c @@ -0,0 +1,42 @@ +/* Reading the per-thread memory protection key, powerpc64 version. + Copyright (C) 2017-2020 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#include <arch-pkey.h> +#include <errno.h> +#include <sys/mman.h> + +int +pkey_get (int key) +{ + if (key < 0 || key > PKEY_MAX) + { + __set_errno (EINVAL); + return -1; + } + unsigned int index = pkey_index (key); + unsigned long int amr = pkey_read (); + unsigned int bits = (amr >> index) & 3; + + /* Translate from AMR values. PKEY_AMR_READ standing alone is not + currently representable. */ + if (bits & PKEY_AMR_READ) + return PKEY_DISABLE_ACCESS; + else if (bits == PKEY_AMR_WRITE) + return PKEY_DISABLE_WRITE; + return 0; +} diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/pkey_set.c b/sysdeps/unix/sysv/linux/powerpc/powerpc64/pkey_set.c new file mode 100644 index 0000000000..20b372ee29 --- /dev/null +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/pkey_set.c @@ -0,0 +1,48 @@ +/* Changing the per-thread memory protection key, powerpc64 version. + Copyright (C) 2017-2020 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#include <arch-pkey.h> +#include <errno.h> +#include <sys/mman.h> + +int +pkey_set (int key, unsigned int rights) +{ + if (key < 0 || key > PKEY_MAX || rights > 3) + { + __set_errno (EINVAL); + return -1; + } + + /* Translate to AMR bit values. */ + unsigned long int bits; + if (rights & PKEY_DISABLE_ACCESS) + /* The PKEY_DISABLE_WRITE bit does not matter. */ + bits = PKEY_AMR_READ | PKEY_AMR_WRITE; + else if (rights == PKEY_DISABLE_WRITE) + bits = PKEY_AMR_WRITE; + else + bits = 0; + + unsigned int index = pkey_index (key); + unsigned long int mask = 3UL << index; + unsigned long int amr = pkey_read (); + amr = (amr & ~mask) | (bits << index); + pkey_write (amr); + return 0; +} |